Influence of excitation on nucleation and growth during quantum dot synthesis in continuous flow

J. Niehaus, D. Ness, A. Becker, H. WellerCAN GmbH, DE

Keywords: quantum dots, synthesis, photochemistry

Summary:

Here we report about the influence of excitation during nucleation and/or growth. For this study a new reactor setup was constructed which is entirely made of glass to allow the excitation during each step of the synthesis. As a light source we have used a LED array emitting at 405 nm with tunable power (max. 6.7 watts). We will show results of Au nanoparticle synthesis in this new flow reactor, with and without excitation during nucleation and/or growth and the influence on size, shape, crystallinity and homogeneity. The same study was repeated for CdSe core particle synthesis to study the differences in their behavior. In addition, we have performed a CdS shell growth step in this reactor as well. An influence on the resulting quantum yield was observed which might be an interesting effect for future improvements of semiconductor nanoparticles.